1. Field of the Invention
THE PRESENT INVENTION relates to a vehicle seat.
2. Description of Related Art
It has been proposed in U.S. Pat. No. 5,378,043 to provide a vehicle seat with a headrest that moves forwardly in the event that a rear impact should occur to minimise the risk of whiplash injuries occurring. The headrest is mounted on upright support bars that are pivotally connected to the upper part of the frame of the backrest of the seat, and which are also connected to a pressure plate which is within the backrest of the seat. In a rear impact situation, when the driver is in a typical position with his head spaced in front of the headrest, initially the torso of the driver will move rearwardly pressing his torso into the backrest of the seat and the pressure plate will thus move rearwardly causing the headrest to move forwardly to ‘catch’ the head of the driver. The head and torso will then be accelerated at the same rate, thus minimising the risk of whiplash injury.
If, however, the head of the driver is close to the headrest when the rear impact occurs, the headrest will impart a substantial forward acceleration to the head of the driver as the torso of the driver moves rearwardly into the seat-back, which may serve to increase the risk of the driver being injured.